Phylogenetic differentiation between Awassi and Hamdani sheep using the mitochondrial 12S rRNA

This study was conducted to assess the role of the mitochondrial 12S rRNA variations in the phylogenetic discrimination between two Iraqi breeds of sheep that differ in geographical distribution. A total of 122 animals (68 Awassi and 54 Hamdani) were included in the study. Direct sequencing of amplicons followed by the construction of a median-joining network and several trees were performed to identify the possible phylogenetic differences between both involved breeds. Genetic diversity, relative frequencies, and analysis of molecular variance (AMOVA) were performed to assess the genetic correlation between both populations. The median-joining network and minimized tree values showed that all observed haplotypes were separated into two groups according to their breed. Comprehensive phylogenetic data revealed only one Asian ancestor for all observed haplotypes. As indicated by AMOVA, the observed diversity was mostly due to between-population variation (1.24836%), while within-population variation (0.91221%) accounted for much less. The currently investigated rRNA amplicons exhibited different mitochondrial manifestations between Awassi and Hamdani breeds. Due to the ability of these 12S rRNA amplicons to mimic the geographical diversity for the currently investigated breeds, it is highly recommended to be used as potent mitochondrial genetic markers among broader ovine sequences.

Automated summary

This study assessed the role of mitochondrial 12S rRNA variations in discriminating between two Iraqi breeds of sheep. It found that there were phylogenetic differences between the two breeds and recommended the use of these 12S rRNA variations as genetic markers.